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View Full Version : Salt Air Ventilation - Slightly Off Topic



Brian_UK
25-09-2006, 11:12 PM
Went to a site today that is alongside a salt water harbour (Portland Harbour, Dorset) to check on some recently installed (one year) ventilation units.

Due to the salt laden atmosphere there is salt encrustation inside the fans boxes as well as corrosion of the galvanised box/fan scroll and blades.

Has anyone any experience or recommendations regarding overcoming the problem.

Should/could a surface treatment be used to protect the metals ?

Is there some means of getting the 'salt' to drop out of the airstream before it hits the fan unit?

Any thoughts would be appreciated.

Snowman123
26-09-2006, 12:25 AM
Think its called blygold its a treatment they spray on condensor coils and evaporators, done a job where i had to cover the inside of the scroll chiller with wax oil. Nightmare stuff its messy but the chiller was on the seafront getting batterd by the water as it came over the sea wall. Try blygold treatment and waxoil thats all you can do. Salt water will rot out most units. Marine paint will help aswell used to paint under side and inside of boats.:)

Abby Normal
26-09-2006, 12:53 AM
I can't be much more than two miles inland, pretty severe salt corrosion problem. A good target is condnesing units, dissimilar metals.

Frequent washing makes a difference.

All coatings ultimately fail.

Aluminum fan wheels perhaps, plastic.

I was discussing this online with a dutch guy before

http://www.thermoguard.net (http://www.thermoguard.net/) went by the name of wouter scheffer

It seemed similar to adsil

Could try adsil, dehli blowers used an 'eisenheiss coating' on the wheels and the shaft, other coatings on the west side of the Atlantic are heresite, bronzglow, electrofin

Carrier's coastal filter was a joke, but maybe a sacrificail aluminum mesh filter upstream may catch some of the mess. How about a big anode on the casing?

Abby Normal
26-09-2006, 01:54 AM
replacement market could be lucrative

Jez
29-09-2006, 10:06 AM
I think that you may also need to filter the air. Vokes used to manufacture salt bag filters. The air would flow up through the bag and collect the salt. When the salt got heavy it would fall back out of the bag.

Of course, it would only work if your fan was able to overcome the resistance and you could find out what happened to Vokes.

chemi-cool
30-09-2006, 09:22 AM
Hi Brian,

SS blades, will solve your first problem. You will still have to clean them once in a while.

Is this air coming in or pulled out?

Chemi:)

Brian_UK
30-09-2006, 12:30 PM
Hi Chemi,

The ductwork layout is:-

High level fresh air intake with circular galvanised duct dropping vertically onto a packaged ventilation unit.

The ventilation unit comprises, from top to bottom, air filter, LPHW heater battery, centrifugal fan, and discharges into more circular ductwork serving changing rooms and toilets.

Abby Normal
30-09-2006, 06:15 PM
If an "LPHW heater battery" is a hyrdronic coil with copper tubes and aluminum fins, good chance the point of contact between the tube and fins is corroded already, unless you have a good coating on that coil.